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Originally Posted by Tormod
I am trying to find evidence for this...can you point me to it?
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The human x chomosome has aobout 155 million base pairs. The y chomosme only about 50 million pairs.
Since females have two x chomsomes and males only one, females will have about 100 million more base pairs. The distinction must also be raised that in female cells onl;y one X chomosome is active, the other beocmes dormant and is refered to as a Barr body. The specific chomosome that is active will vary from cell to cell. That is to say that different x chomosomes are active in different cells. A good example of this is tortoise shell coloration in cats. Coloration is carried on the x chomosome in cats. The motled appearance of tortoise shell cats is caused by different x chomosomes being active in different cells producing the coloration. Males cannot be tortoise shell (although it might occur if there is a feline variation of Klienfelter's Disease. A genetic anomoly that produces XXY males in humans).
So in actuality, while females have more geteic material in their cells, males actually have more active genetic matierial because both the X and Y genes are active. So in realitty males have more funtional DNA in their cells (about 50 million more base pairs).
http://ghr.nlm.nih.gov/chromosome=Y
http://ghr.nlm.nih.gov/chromosome=X
